Railroads are a fundamental, strategic, pioneering, and essential industry for the national economy. They are a significant artery for economic and social development.
Railroad cargo transportation is one of the primary modes of modern transportation and one of two foundational modes of land-based cargo transportation. It plays an essential role in the transportation industry and is increasingly important.
Railroad transportation has the advantage of regularity and low cost due to its ability to be less affected by weather and natural conditions. Its transport capacity and single car load are also significant advantages. Rail transport can carry almost any commodity with minimal weight and volume restrictions, making it a more versatile transportation method than road or air transport.
The railroad industry has explored every possible means to tap into its potential and improve efficiency to ensure the transportation of key national materials. The railroad's vital role in promoting economic and social development has been fully demonstrated through substantial increases in passenger and freight traffic while ensuring transport safety. Railroad transportation has also played an important role in easing tension in coal, electricity, and oil transportation while ensuring the normal life of the people and economic and social development.
The track is a crucial part of the line equipment, and its role is to guide the locomotive vehicle operation, directly bearing the locomotive vehicle load and distributing it to the roadbed or bridge, and tunnel buildings. The track structure must have sufficient strength, stability, and smoothness to ensure that the rolling stock runs according to the maximum load and maximum allowable speed. The track structure can be divided into ballasted track structure and ballastless track structure.
The ballasted track consists of a ballast bed, rail sleeper, rail, joint parts, track strengthening equipment, and turnout, among others. The ballastless track is a form of track structure composed of a concrete or asphalt mixture instead of a bulk ballast bed. The ballastless track is composed of a ballast bed, rail, joint parts, and turnouts, among others.
The steel rail is the most crucial component of the track, directly bearing the load of the train, guiding the train by relying on the interaction between the inner side of the railhead and the rim of the rolling stock, and distributing the rolling stock load and transferring it to the rail sleeper through its own stiffness and elasticity. As the axle weight of the rolling stock gradually increases and the speed of traffic increases, the rail load also increases. Therefore, the material and strength of the rail have higher requirements.
The rail sleeper, on the one hand, bears the force of the rolling stock down the rail and transfers it to the bed. On the other hand, it fixes the rail in the specified position through fasteners to maintain the gauge, rail bottom slope, curve super high, and others, forming the rail row with the rail and combining with the bed to provide the required bed longitudinal and transverse resistance.
The ballast bed is the foundation of the rail sleeper, on which a certain number of rail sleepers are arranged at prescribed intervals to provide the elasticity and longitudinal and transverse resistance of the track, and to facilitate drainage and correction of the plane and longitudinal section of the track. The ballastless bed is a type of bedform with concrete instead of a rail sleeper and bulk ballast. The turnout is composed of a rutting device, a rut fork, and a rail guard, connecting parts, and its primary function is to guide the train from one line to another line.
The connecting parts include joint connecting parts and fasteners. The joint parts' role is to realize the reliable connection between rails and maintain the continuity and integrity of the rails. The fasteners' role is to realize the reliable connection between rails and rail sleepers, prevent longitudinal and transverse displacement of rails relative to rail sleepers, ensure the normal gauge, and provide insulation, and elasticity. Anti-climbing equipment consists of an anti-climbing device and anti-climbing support, used to strengthen the rail and rail sleeper connection and improve the line resistance to rail crawling ability. For the line using elastic fasteners, can not set up anti-climbing equipment.
